minibuffer-completion-help, metadata and determining completions sort order

minibuffer-completion-help, metadata and determining completions sort order

[T. V. Raman]

I'm having a hard time understanding how one provides custom
metadata to completion-all-completions and friends. Also, looking
at the code in minibuffer-completions-help, I see that the
metadata can provide  a custom sort function -- sounds
good. However the specific use case I want is the ability to not
sort the completions -- Ineed this for implementing Google
Suggest in the minibuffer. I had asked about this many moons ago
and Stefane had said that the code in minibuffer.el would be
changing to support this, assuming the metadata functionality is
to address that  and other use cases?  Anyway, I'd like the
ability to  be able to set things up for Google Suggest so the
completions list goes through unmolested, and as things stand,
Isuppose I could provide a no-op sorter once I figure out to
supply the metadata; however that still feels wasteful since we
would end up traversing the list of completions for no reason ---
there is no option to avoid the sort call in minibuffer-completions-help

-- 
Best Regards,
--raman

Re: minibuffer-completion-help, metadata and determining completions sort order

[Thierry Volpiatto]

"T. V. Raman" <tv.raman.tv@gmail.com> writes:

> I'm having a hard time understanding how one provides custom
> metadata to completion-all-completions and friends. Also, looking
> at the code in minibuffer-completions-help, I see that the
> metadata can provide  a custom sort function -- sounds
> good. However the specific use case I want is the ability to not
> sort the completions -- Ineed this for implementing Google
> Suggest in the minibuffer. I had asked about this many moons ago
> and Stefane had said that the code in minibuffer.el would be
> changing to support this, assuming the metadata functionality is
> to address that  and other use cases?  Anyway, I'd like the
> ability to  be able to set things up for Google Suggest so the
> completions list goes through unmolested, and as things stand,
> Isuppose I could provide a no-op sorter once I figure out to
> supply the metadata; however that still feels wasteful since we
> would end up traversing the list of completions for no reason ---
> there is no option to avoid the sort call in minibuffer-completions-help

BTW Anything have already google suggestions.

-- 
A+ Thierry
Get my Gnupg key:
gpg --keyserver pgp.mit.edu --recv-keys 59F29997 

minibuffer-completion-help, metadata and determining completions sort order

[raman]

                                                                   


-- Thierry Volpiatto <thierry.volpiatto@gmail.com>                      10:23a
   To: emacs-devel@gnu.org

TB> BTW Anything have already google suggestions.

What is "anything"?

Am having a hard time parsing your reply:-)


--
A+ Thierry
Get my Gnupg key:
gpg --keyserver pgp.mit.edu --recv-keys 59F29997



-- 
Best Regards,
--raman

-- 
Best Regards,
--raman

Re: minibuffer-completion-help, metadata and determining completions sort order

[Stefan Monnier]

> I'm having a hard time understanding how one provides custom
> metadata to completion-all-completions and friends.

The completion table needs to provide the metadata.

> Isuppose I could provide a no-op sorter once I figure out to
> supply the metadata; however that still feels wasteful since we

If the sort function is `identity' it will leave this as-is.

> would end up traversing the list of completions for no reason ---

Why would you think it needs to traverse the list of completions?
[ Not that it would matter anyway, since the list has already been
  traversed before and will be traversed again afterwards, any
  potential slowdown should be negligible. ]


-- Stefan

Re: minibuffer-completion-help, metadata and determining completions sort order

[Thierry Volpiatto]

raman <tv.raman.tv@gmail.com> writes:

> TB> BTW Anything have already google suggestions.
>
> What is "anything"?
Get the files here:
http://repo.or.cz/w/anything-config.git

Have infos here: (not updated)
http://www.emacswiki.org/emacs/Anything

The mailing list is here:
http://groups.google.com/group/emacs-anything?hl=en

or in gmane at gmane.emacs.anything

> Am having a hard time parsing your reply:-)
Sorry.;-)

-- 
A+ Thierry
Get my Gnupg key:
gpg --keyserver pgp.mit.edu --recv-keys 59F29997 

minibuffer-completion-help, metadata and determining completions sort order

[T.V. Raman]

Stefan, So the metadata gets placed as a property on the table?

Also I said the list would get traversed even if the sort
function was identity because the code does a funcall of the sort
function provided, but perhaps that's not a big issue. Some
examples on providing metadata would really help -- I've never
fully understood the completions code -- especially with respect
to the table and mode arguments.

-- 
Best Regards,
--raman


On 6/18/11, Stefan Monnier <monnier@iro.umontreal.ca> wrote:
>> I'm having a hard time understanding how one provides custom
>> metadata to completion-all-completions and friends.
>
> The completion table needs to provide the metadata.
>
>> Isuppose I could provide a no-op sorter once I figure out to
>> supply the metadata; however that still feels wasteful since we
>
> If the sort function is `identity' it will leave this as-is.
>
>> would end up traversing the list of completions for no reason ---
>
> Why would you think it needs to traverse the list of completions?
> [ Not that it would matter anyway, since the list has already been
>   traversed before and will be traversed again afterwards, any
>   potential slowdown should be negligible. ]
>
>
> -- Stefan
>

minibuffer-completion-help, metadata and determining completions sort order

[raman]

Stefan, So the metadata gets placed as a property on the table? 

Also I said the list would get traversed even if the sort
function was identity because the code does a funcall of the sort
function provided, but perhaps that's not a big issue. Some
examples on providing metadata would really help -- I've never
fully understood the completions code -- especially with respect
to the table and mode arguments.

-- 
Best Regards,
--raman

-- 
Best Regards,
--raman

Re: minibuffer-completion-help, metadata and determining completions sort order

[Stefan Monnier]

> Stefan, So the metadata gets placed as a property on the table?

No, the table has to be a function (completion tables can be
represented in many different ways: hash-table, obarray, list, alist,
and function).
Take a look at `completion-metadata' to see how the metadata
is extracted (the Lisp manual still doesn't have the corresponding
description :-( ).

> Also I said the list would get traversed even if the sort
> function was identity because the code does a funcall of the sort
> function provided, but perhaps that's not a big issue.

The "sort function" doesn't have to sort, it just takes a list and must
return a list, it can return the list it receives without looking at it,
as is the case if that function is `identity'.


        Stefan